On

On( )

switch on the interactive trace. The output is printed in the defined out stream.

On({head1, head2,... })

switch on the interactive trace only for the heads defined in the list. The output is printed in the defined out stream.

On({head1, head2,... }, Unique)

or

On(All, Unique)

switch on the interactive trace only for the defined head s. The output is printed only once for a combination of unevaluated input expression and evaluated output expression.

Examples

On() enables the trace of the evaluation steps.

>> On()
  On() --> Null

>> D(Sin(x)+Cos(x), x)

  NotListQ(x) --> True

  D(x,x) --> 1

  D(x,x)*(-1)*Sin(x) --> (-1)*1*Sin(x)

  (-1)*1*Sin(x) --> -Sin(x)

  D(Cos(x),x) --> -Sin(x)

  NotListQ(x) --> True

  D(x,x) --> 1

  Cos(x)*D(x,x) --> 1*Cos(x)

  1*Cos(x) --> Cos(x)

  D(Sin(x),x) --> Cos(x)

  D(Cos(x)+Sin(x),x) --> -Sin(x)+Cos(x)

Cos(x)-Sin(x)

Off() disables the trace of the evaluation steps.

>> Off()

>> D(Sin(x)+Cos(x), x)
Cos(x)-Sin(x)

Related terms

Off

Implementation status

• ☑ - partially implemented

Github

• Implementation of On